13-EHS Section 7 Flashcards
What is not one of the primary cause of injury and death when it comes to electrical hazards in firefighting?
a) Indirect contact with energized wires
b) Lack of visibility
c) Contact through equipment
d) Muscle contractions
D
The greatest possibility for injury and death can be attributed to the direct body contact with energized wires or contact through equipment. In limited visibility, walk with the palms of your hands facing towards you.
When working near overhead power lines, what is the recommended minimum distance of approach for all persons, tools, and equipment on an aerial platform?
a) 1 meter
b) 3 meters (10 ft)
c) 5 meters
d) 8 meters
B
Minimum 3m (10 t) from working zone
What precaution should be taken if safe limits of approach cannot be maintained when working near overhead power lines?
a) Request additional personnel
b) Use alternative means to fight the fire
c) Increase the height of the aerial platform
d) Ignore the limits of approach
B
If safe limits of approach cannot be maintained, either have the electrical utility disconnect all
sources of electricity from the overhead power lines or use alternative means to ight the ire. For
known difficult situations preplan the ire or emergency response
Why is it important to know the location of power lines before setting up aerial equipment?
a) To avoid interfering with radio signals
b) To ensure proper communication with the team
c) To prevent damage to power lines and supporting structures
d) To calculate the distance to the nearest fire hydrant
C
Ensure vehicles and equipment are
positioned where they will be safe.
In the event the growth of the ire
results in damage to either power
lines or supporting structures use
collapse zone distances or Operational
Guidelines for apparatus placement.
When working in close proximity to power lines, what role does the second firefighter play?
a) Hose management
b) Signaller/Observer
c) Incident Commander
d) Equipment operator
B
You must use a second fire fighter
as a dedicated signaler/observer when
working in close proximity to power lines.
The signaler/observer watches the ladder
(boom) and warns the operator if the
boom gets close (3m)
What is the minimum distance recommended when working overtop power lines using aerial equipment?
a) 1 meter
b) 3 meters (10 ft)
c) 5 meters
d) 10 meters (33 ft)
B
The signaler/observer watches the ladder
(boom) and warns the operator if the
boom gets close (3m)
How should emergency responders shut off the electrical supply to a building when needed?
a) Pull the meter to disconnect the power
b) Shut off the main power switch or contact the electrical utility
c) Disconnect individual circuits first, then shut off the main switch
d) Use emergency generators to override the power supply
B
When the electrical supply to the building must be shut of, either shut of the main power switch
or have the local electrical uility disconnect the supply. Caution is required when shuing of the
main power switch to the building since the “line side” of the switch and the incoming wires are sill
energized.
Why should emergency responders wear dry leather gloves when turning off the main power switch?
a) To improve grip
b) To avoid electrical shock
c) To minimize the risk of explosive flash
d) To maintain a professional appearance
B
When turning of the main power switch, wear dry leather gloves.
What is the recommended practice for shutting off the main power switch to minimize the possibility of an explosive flash?
a) Use both hands to turn it off quickly
b) Keep the face towards the panel
c) Turn it off with a wet cloth in hand
d) Use left hand and turn away
D
Use your letf hand and turn away
when shutting of the power. Alternatively, keep your back towards the wall with your face turned
away from the panel and then shut the panel of. This way your forearm will be propelled in a normal forward position minimizing injury if there is an explosive lash.
In flooded buildings, what signs may indicate electrically charged floors?
a) Unusual sparking
b) Strong odor of chemicals
c) Presence of gas leaks
d) Elevated humidity levels
A
Signs of electrically charged floors could include unusual sparking, unconscious victims or persons receiving shocks from equipment touching the wet area. If the building is flooded, best practice is to disconnect power from outside prior to entry, as these signs are not always present.
What is the best practice for disconnecting power when entering a wet or flooded building?
a) Disconnect power from outside the building
b) Request assistance from the fire department
c) Use a wooden stick to flip the circuit breakers
d) Wait for the water to recede naturally
A
If the building is flooded, best practice is to disconnect power from outside prior to entry, as these signs are not always present.
How should emergency responders handle breakers after shutting off electrical hazards?
a) Turn them on immediately
b) Leave them in the off position
c) Toggle them on and off repeatedly
d) Notify the Electrical Safety Authority for re-energizing
B
In the event Emergency Responders have shut of
electrical hazards, they are to leave the breakers in the of position. Emergency Responders are NOT authorized to turn on (reenergize) the equipment as the site’s electrical equipment needs to be inspected by the Electrical Safety Authority.
What hazards are associated with electrical vaults in high-rise buildings?
a) Toxic gases only
b) Electrical shock only
c) Explosion, fire, and toxic gases
d) Falling debris only
C
Hazards include large volumes of thick toxic black smoke, ire, explosion, lying debris and possibly flammable gases. An environmental hazard (methane) should be considered since floor drains may be directly connected to storm sewers
Why should emergency responders not attempt to open vault doors marked “DANGER HIGH VOLTAGE” without proper authorization?
a) To avoid tripping the alarm
b) To prevent explosive flashes
c) To maintain security measures
d) To avoid introducing air for a potential explosion
B
The access doors are typically marked “DANGER HIGH VOLTAGE” and contain utility contact information. Emergency responders should not access a vault unless the local utility has been notified and has confirmed the power has been disconnected
What is the recommended action if thick black smoke is emitting from an electrical vault’s ventilation grate?
a) Open the grate to allow ventilation
b) Evacuate the building and keep the vault door closed
c) Attempt to remove the ventilation grate
d) Ignore it and continue with firefighting operations
B
If smoke is seen exiting the ventilation grates, evacuate the building and keep vault door(s) closed until the local utility has disconnected the power.
